The Maryland Hospital Association has sent a letter to state health officials saying it will not support a proposal that would link medical spending to the state's economic growth. The state presented the proposal to the Centers for Medicare and Medicaid Services in March as part of an application to update its Medicare waiver, an agreement with the federal government unique to Maryland that allows the state to set uniform hospital rates. The hospital association has said in the past the proposal raises concerns, but the April 25 letter is the first time the group publicly said it would not support it.